Then I came back to check another page, where I wanted my 3 module layout to work (3-6-3).
This page have nothing published in sidebar-a so, I was assuming that my sidebar-b was on the right of my mainbody because I had set my sidebar-a to the left in the 2 module layout.
Surprise, my modules published in sidebar-b skip to the left.
hi there,
if you have a module in sidebar-b and NO module in sidebar-a, then the sidebar-b module will render as a sidebar-a module, therefore it shows on the left and not on the right. so the override you created is the only way to have the sidebar-b on the right side like you wanted.
hope this helps, kat